Short life paper size from modified polyalkylene-imines

ABSTRACT

Unique water-soluble polymers are prepared by reacting a polyalkylenepolyamine or a polyalkylenimine with an epoxide or an activated aziridine; the epoxide and aziridine rings are each connected to a hydrocarbon radical having at least eight carbon atoms through generally an ether, ester, carboxamide or phosphoramide linkage. The polymers are particularly useful as temporary paper sizes, i.e., the polymers impart a sizing effect which disappears after some days without affecting the absorbency characteristics of the paper after that time.

United States Patent Longoria, III et al.

[ 1 Jan. 18,1972

[541 SHORT LIFE PAPER SIZE FROM MODIFIED POLYALKYLENE-IMINES [72]Inventors: Juan Longoria, III; William P. Coker,

both of Lake Jackson, Tex.

[73] Assignee: The Dow Chemical Company, Midland,

Mich.

[22] Filed: June 27, 1966 [2]] Appl. No.: 560,640

[52] US. Cl. ..260/2 BP, 117/155 R, 162/168, 260/2 EN, 260/29.2 EP,260/29.2 N, 260/482 R,

[51 Int. Cl ..C08g 33/08 [58] Field of Search... ..260/2 EP, 2 EN, 2 P,47 EP, 260/561, 584, 959, 482; 117/155; 162/168 [56] References CitedUNITED STATES PATENTS 2,272,489 2/1942 Ulrich ..260/239 2,296,225 9/1942Ulrich 2,852,467 9/1958 Hollyday ..252/34 3,277,128 10/1966 Van derVoort ..260/404.5 3,355,437 11/1967 Tesoro et a1. ..260/77.5

OTHER PUBLICATIONS L. E. Davis, Polyethylenimine in Davidson-SittigWater- Soluble Resins, 2nd ed., 1966, Reinhold, pp, 216- 219 and 222-223.

Primary Examiner--Wil1iam H. Short Assistant ExaminerE. NielsenAttorney-Griswold & Burdick and Theodore Post [5 7] ABSTRACT 20 Claims,6 Drawing Figures BACKGROUND OF THE INVENTION The present inventionrelates to a process for producing a water-soluble polyalkylenimine orpolyalkylenepolyamine having long chain groups substituted on the aminenitrogen and to the polymers so produced. More particularly, it relatesI to the reaction product and process for chemically combining apolyalkylenimine or polyalkylenepolyamine and an epoxy or activatedaziridinyl monomer having an alkyl, aryl, alkaryl, or an ester groupcontaining from about eight to about 20 carbon atoms. The water-solublepolymers of this invention possess a unique property as paper sizes.They impart a temporary sizing effect which disappears after some dayswithout affecting the absorbency characteristics of the paper after thattime They are also useful for improving the wet and dry strength ofpaper and as a drainage aid in paper production.

Polyalkylenimine (hereinafter PAI) and kylenepolyamine (hereinafterPAPA) are highly substantive to cellulosic pulp and paper. For thisreason, the use of PA! and PAPA in the manufacture of paper, forexample, as retention agents and for improving the strength ofcellulosic polyalproducts, is known in the art.

In order to improve the effect of PAI and PAPA in the manufacture ofpaper, various modifications of these polymers have been proposed. Forexample, US. Pat. No. 2,772,966, discloses a paper sizing compositionprepared by heating a major amount of an ester gum with a minor amountof a water-soluble polyalkylenepolyamine. British Pat. No. 1,800,464,discloses water-soluble reaction products of PAI with epichlorohydrin.These compositions are useful for improving the wet strength of paper.

Paper sizes having a temporary efiect, i.e., those which reduce themoisture absorption qualities of paper for a short time, are desirousfor certain purposes. Such short life paper sizes would be well suited,for example, for the production of paper towels, absorbent tissue,cigarette paper, and the like.

Temporary sizing will allow printing on such paper without affecting theabsorbency qualities for the final use.

SUMMARY OF THE INVENTION It has now been discovered that certain novelwater-soluble, modified polyalkylenimines and polyalkylenepolyamines ofthis invention function well as short life paper sizes. The novelpolymers of this invention are prepared by chemically combining withagitation from about 10 percent by weight to about 50 percent by weight,total reactant basis, of an activated aziridinyl or epoxy monomer havingan alkyl, aryl, alkaryl, or an ester group containing from about eightto about 20 carbon atoms with from about 90 percent by weight to about50 percent by weight, total reactant basis, of a watersoluble PAI orPAPA.

While the mechanism of the reactions involved in the present inventionare not fully understood and applicants do not wish to be bound by anyparticular reaction theory, it is believed that the epoxy and aziridinylrings of the monomers open and attach to both primary and secondaryamine nitrogens in the PAI or PAPA. Thus, in the case of an epoxymonomer, a polymer of random structure having the following recurringgroups is probably formed:

wherein R is an alkyl, aryl, alkaryl, or an acyl group containing fromabout eight to about 20 carbon atoms, R is hydrogen or an alkyl group offrom one to four carbon atoms, and the ratio of x to y depends on therelative ratio of reactants combined as indicated above. In the case ofan activated aziridinyl monomer, a polymer of random structure havingthe following recurring groups probably results:

wherein X is carbon or phosphorus, Y is oxygen or sulfur, n is 1 when Xis carbon and 2 when X is phosphorus, R,, x and y have the same meaningas indicated in the case of the epoxy monomer, R is hydrogen or an alkylgroup having from one to four carbon atoms, and R is an alkyl, aryl,alkaryl, alkoxy, aryloxy or alkaryloxy group of from about eight toabout 20 carbon atoms.

In general, any water-soluble PAI or PAPA is suitable for the practiceof the present invention. Thus, suitable polyalkylenepolyamines includediethylenetriamine, triethylenetetraamine, tetraethylenepentamine, andthe analogous polypropylenepolyamines and polybutylenepolyamines. Highermolecular weight polyal kylenepolyamines, for example, those havingmolecular weights up to 200,000 and higher are also suitable for thepractice of this invention. They may be prepared by polymerizing thepolyalkylenepolyamines listed above.

Suitable polyalkylenimines include water-soluble polyethylenimines(hereinafter PEI), polypropylenimines, and polybutylenimines havingmolecular weights from under 1,000 to 1,000,000 and higher. Methods forpreparing such PAI are known in the art. The polymerization ofalkyleneimines has been reviewed, for example, by Jones, ThePolymerization of Olefin lmines, in P. H. Plesch, ed., The Chemistry ofCationic Polymerization, New York, MacMillan (l963 Pages 52 l-534.

In general, monomers having a terminal activated aziridinyl group or aterminal epoxy group and having an alkyl, aryl, alkaryl, or an estergroup containing from about eight to about 20 carbon atoms are suitablefor reaction with the PAI or PAPA to produce the polymers of thisinvention. Examples of suitable epoxy monomers include:l-(p'dodecylphenoxy)-2,3- epoxy propane, l-(o-sec-butylphenoxy)2,3-epoxypropane, 3- (2,3-epoxy propoxy)-2-hydroxypropyl stearate, 2,3-epoxypropyl benzoate, 2,3-epoxy propyl octadecenate, and the like. Thepreferred epoxy compounds are those having the general formula:

wherein R is an alkyl, aryl, alkaryl, or an acyl group containing fromabout eight to about 20 carbon atoms. Methods for preparing epoxycompounds useful for this invention and examples of suitable epoxycompounds are disclosed, for example, by A. M. Paquin,Epoxydverbindungen und Epoxydharze, Springer-Verlag (1958), especiallypage 247. The terminal epoxy group will open and attach to the polymericamine chain without the presence of an activating bond or groupproximate to the epoxy group.

As used herein, the term activated aziridinyl monomer refers to thoseaziridine compounds having a bond proximate thereto which makes theaziridine ring reactive so that it opens readily to react with thepolymeric amines used herein. Activated aziridinyl monomers operable forthe present invention may be represented by the general formula:

Y CHR:

wherein X is carbon or phosphorus, Y is oxygen or sulfur, n is 1 when Xis carbon and 2 when X is phosphorus, R is as defined above and R ishydrogen or an alkyl group of from one to four carbon atoms. Examples ofsuitable activated aziridinyl monomers include dodecyl l-aziridinylcarboxylate, didecyl l-aziridinyl phosphonate, octadecyl l-aziridinylcarboxylate, phenyl l-aziridinyl carboxylate, didecyl l-aziridinylphosphine sulfide, and the like. Such aziridinyl compounds may beprepared by methods reviewed in H. Bestian et al., Ann. 566, 210-44(1950).

In practice, the novel polymers of the present invention are prepared bycombining the proportions by weight of the PM or PAPA discussedpreviously, stirring the mixture until homogeneous, and allowing themixture to stand for a sufficient time to allow completion of thereaction, i.e., for about 8 to about 20 hours. For PAl having amolecular weight above about 3,000 an inert solvent in which both thePA] and the epoxy or activated aziridinyl monomer are dispersible ispreferably used. Suitable specific examples of such solvents includealcohols containing from one to about four carbon atoms such asmethanol, ethanol, propanol, butanol, and the like; inert chlorinatedsolvents such as methylene chloride, ethylene chloride,perchloroethylene, and the like; aromatic hydrocarbons, such as toluene,benzene, and the like. With PAl having a molecular weight below about3,000 and for PAPA, no solvent is needed since these polymers have lowenough viscosities to serve as solvents themselves.

While the reaction between the activated aziridinyl or epoxy monomer andthe PM or PAPA can be accomplished at substantially room temperature,temperatures from about up to as high as 95 C, can be used. Preferably,the temperature of the reaction system is within the range from about 20to about 60 C.

The products of this invention are useful both as short life paper sizesand for improving the wet and dry strength properties of paper,paperboard and similar cellulosic materials. They may be applied to anyof the stocks commercially used for the manufacture of paper, but theyare preferably used to treat papers in which absorbency is desired inthe final product with sizing desired for processing.

The polymers may be applied to paper by any of the commonly knownmethods. They are particularly adapted for application by the beater"method in which the size is added to a dilute aqueous suspension ofcellulosic fibers and deposited on the fibers before they are made intopaper. Absorption of the size is rapid, and is often complete within 10seconds, permitting the addition of the sizing agent at any desiredpoint ahead of the wire, even in high speed papermaking machines. Wherefillers are used, the fillers are more advantageously added afterabsorption of the size than before.

The sizes may also be applied by the tub" sizing or impregnation method.1n the tub method, the paper web is passed into an aqueous dispersioncontaining from about 0.05 percent by weight to about 1.0 percent byweight of the size, excess liquid is squeezed ofi by rolls, and thepaper is dried. 1n the impregnation method, the aqueous dispersion orsolution of the polymer is sprayed upon one or both sides of the paper,which is then squeezed and dried as in the case of tub sizing. ln bothinstances, rapid and uniform pickup of the size takes place even whenvery dilute solutions are used because of the extremely cationic,cellulose-substantive nature of the size.

The preparation of paper according to this invention therefore in itsbroadest aspect consists in absorbing the requisite quantities of theaforementioned polymers upon the cellulosic fibers and drying thefibers. In contrast to many sizing agents and strength improvers forpaper, curing of the polymers on the cellulosic fibers is not requiredto obtain the beneficial properties obtained from the polymers of thisinvention.

The invention will be further described and illustrated by the followingspecific examples which show the preparation of polymers representativeof the present invention and the application thereof to paper. In orderto demonstrate the sizing obtained through the use of these polymers,paper treated with them was evaluated by the Cobb test and the inkpenetration test. The Cobb test is a measure of the weight of water orother test liquids that will be absorbed by the paper in a given periodof time. The test is conducted by first weighing a sample 12.5centimeters square, covering its central portion with a metal cylinder10 centimeters in diameter and pouring 25 ml. of water or other testliquid into the cylinder. After 15 minutes (or other predetermined testtime) the excess water is poured off, surface moisture is removed fromthe paper, and the sample is again weighed. The weight of the absorbedwater is multiplied by 8 and the test results are reported as grams ofmoisture absorbed by a sheet 100 centimeters square.

FIGS. l-5 represent semilogarithmic plots of Cobb sizing values obtainedfor different concentrations of the polymers of this invention inaqueous solution prepared from different percentages by weight of theactivated aziridinyl or epoxy monomer and PEI. The Cobb sizing valuesare plotted on the logarithmic scale as indicated, and the percentagesby weight of the epoxy or activated aziridinyl monomer and the PEI usedto prepare the polymers is plotted on the arithmetic scale. The higherthe Cobb sizing value, the less desirable is the sizing agent. A sampleof unsized kraft paper will absorb about 1,200 g. of water per squaremeter while kraft paper treated with a good sizing agent will absorbless than about 100 g. of water per square meter. These valuescorrespond to the Cobb sizing values. The graphs will be explained inmore detail in the examples below.

The ink penetration test is a measure of the time in seconds requiredfor ink to soak through the paper, as measured by a photovolt meter witha tristimulus filter on the photoelectric cell. This time will vary froma few seconds in the case of the controls to well over 1,000 seconds inthe case of hard sized papers. The test is conducted by first fasteninga 2- by 2-inch sample of the paper to be evaluated on top of the cell bymeans of a ring clamp paper holder. A black cavity is then placed on topof the paper holder, and the galvanometer is adjusted to 100 by means ofthe sensitivity controls. The black cavity is removed, and ink is pouredon the exposed paper inside the ring clamp until the ink level is evenwith the top of the clamp. The elapsed time until the galvanometer reads50 is then measured. In order to reduce the time for testing highlysized paper, the galvanometer reading is made after 1,000 seconds whenthe galvanometer has not dropped to 50 by that time (e.g., 1,000 secondsat percent). In this test, the higher the value in seconds or the higherthe reading on the galvanometer after 1,000 seconds, the better is thesizing.

The following examples describe completely representative specificembodiments of the invention claimed and the best modes contemplated bythe inventors for practicing the claimed invention. The scope of theinvention is limited, however, only by the scope of the claims appendedhereto.

EXAMPLE 1 Into a vessel equipped with stirring means were placed 25 g.of a solution of PE! having a molecular weight of about 1,000,000 asdetermined by viscosity measurement and consisting of 25 percent byweight solids in n-butanol. To this was added 6.2 g. of dodecyll-aziridinyl carboxylate (dodecyl aziridinyl formate). The weight ratioof reactants was 50 percent PEI to 50 percent dodecyl aziridinylformate. The above mixture was stirred until homogeneous and allowed tostand at room temperature (25 C.) for 16 hours.

The resulting polymer product was evaluated as a paper size by treatingunsized, unbleached kraft paper with a size bath consisting of anemulsion of 0.05 percent by weight solids of the above product in water.A 6- by 6-inch sample of paper was completely submerged in this bath andallowed to remain for one minute. At the end of this time, the paper wasremoved from the bath, blotted ro remove excess sizing solution, anddried. The sizing properties of the polymers were evaluated by the Cobbtest described previously. A sample of paper treated in this manner hada Cobb sizing value of 23, while an unsized sample of the same paper hada Cobb sizing value of 1,200. As used herein, the polymers areconsidered to give good sizing results when they give a Cobb sizingvalue of less than about 100.

Similar polymers were prepared from percent by weight dodecyl aziridinylformate and 90 percent by weight PEI, and from 30 percent by weightdodecyl aziridinyl formate and 70 percent by weight PEI. Each of thepolymers prepared above was evaluated as a paper size at 0.05 percent byweight, 0.15 percent by weight, and 1 percent by weight aqueous solutionconcentrations. FIG. 1 is a graph of the results obtained.

Best results appear to be obtained with this polymer composition in themore dilute solution prepared from about percent by weight to about 50percent by weight of the dodecyl aziridinyl formate and from about 80percent by weight to about 50 percent by weight of the PEI.

Similar advantageous results were obtained when paper was sized with thereaction product of PEI having a molecular weight of about 5,000 anddodecyl aziridinyl formate.

EXAMPLE 2 Water-soluble polymers were prepared according to theprocedure of example 1 from PEI having a molecular weight of about1,000,000 as determined by viscosity measurements andl-(p-dodecylphenoxy)-2,3-epoxy propane (dodecylphenyl glycidyl ether);from 85.5 percent by weight PEI and 14.5 percent by weight dodecylphenylglycidyl ether; from 73.5 percent by weight PEI and 26.5 percent byweight dodecylphenyl glycidyl ether; and from 53 percent by weight PEIand 47 percent by weight dodecylphenyl glycidyl ether.

These polymers were evaluated as paper sizing agents according to theprocedure in example 1 as aqueous solutions containing 1 percent byweight, 0.15 percent by weight, and 0.05 percent by weight of thepolymers. The results are shown in FIG. 2.

As shown by FIG. 2, good sizing results are obtained with thePEI-dodecylphenyl glycidyl ether polymer solution in the more diluteconcentrations containing from about 10 percent by weight to about 40percent by weight dodecylphenyl glycidyl ether and from about 90 percentby weight to about 60 percent by weight PEI, and with the moreconcentrated solution, good sizing results are obtained throughout thecomposition range.

EXAMPLE 3 Polymers were prepared as in examples 1 and 2 from PEI and3-(2,3-epoxypropoxy)-2-hydroxypropyl stearate (stearic acid diglycidylether ester). The polymers were prepared from 10 percent by weight ofthe monomer and 90 percent by weight PEI, from percent by weight monomerand 70 percent by weight PEI and from 50 percent by weight monomer and50 percent by weight PEI. Each of these polymers was tried as a papersize at 0.05 percent by weight, 0.15 percent by weight and l-percent byweight aqueous solution concentrations. The results are shown in FIG. 3.FIG. 3 shows that good sizing values can be obtained from thePEI-stearic acid diglycidyl ether ester polymer prepared from about 20percent by weight to about 50 percent by weight of the stearic aciddiglycidyl ether ester and from about 80 percent by weight to about 50percent by weight of the PEI.

EXAMPLE 4 As in examples 1-3, polymers were prepared from PEI andl-(o-sec-butylphenoxy)-2,3-epoxy propane. The polymers were preparedfrom 10 percent by weight of the monomer and 90 percent by weight PEI,from 30 percent by weight monomer and percent by weight PEI, and from 50percent by weight monomer and 50 percent by weight PEI. These polymerswere evaluated as paper sizes, giving the results shown in FIG. 4. FIG.4 shows that the more dilute polymer solution prepared from about 15percent by weight to about 50 percent by weight of the 1-(o-sec-butylphenoxy)-2,3-epoxy propane and from about percent by weightto about 50 percent by weight PEI gave good sizing values. Good sizingvalues were also obtained with the 1 percent by weight solution preparedfrom 50 percent by weight of the monomer and 50 percent by weight of thePEI.

EXAMPLE 5 As in examples l-4, polymers were prepared from PEI anddidecyl l-aziridinyl phosphonate. The polymers were prepared from 10percent by weight of the monomer and percent by weight PEI, from 30percent by weight monomer and 70 percent by weight PEI, and from 50percent by weight monomer and 50 percent by weight PEI. These polymerswere evaluated as sizing agents with the results shown in FIG. 5. Thesepolymers appear to give good sizing results in both the dilute and themore concentrated solutions through the whole range evaluated.

Similar advantageous results are obtained when diethylenetriamine,triethylenetetraamine, tetraethylenepentamine, the analogouspolypropylenepolyamines, polybutylenepolyamines, polypropylenimines, andpolybutylenimines are substituted for the PEI in examples 1-5.

EXAMPLE 6 For comparative purposes, PEI and wood rosin were combinedaccording to the procedures used in examples l-5, and the resultingpolymers evaluated as a paper size. The results are shown in FIG. 6.Cobb sizing values below were obtained from compositions prepared with50 percent by weight rosin and 50 percent by weight PEI in the 0.05percent by weight solution and the 0.15 percent by weight solution. TheCobb sizing value for the other percentages and concentrations range upto 1,000 and higher.

EXAMPLE 7 The effectiveness of a polymer prepared from 50 percent byweight of didecyl l-aziridinyl phosphonate and 50 percent by weight PEIaccording to the procedure of example 5 for addition by the beatermethod was evaluated. The polymer was added as a 1 percent by weightwater solution to 250 ml. of a dilute paper stock containing 1.2 g. ofbone dry unbleached sulfite spruce pulp (400 ml. Canadian StandardFreeners). The slurry was stirred for 1 minute, then a handsheet wasfonned on a standard British Handsheet Machine (T.A.P.P.I. Method T205).The treated sheets were dried for 1 minute at C. The dried sheets wereevaluated by the ink penetration test described previously, with theresults shown below in table I. The sizing values shown below wereobtained first, at the time of preparation, and second, after 15 days ofstorage at room temperature (i.e., about 25 C.

TABLE I Galva- Seconds Galva- Seconds nometer for ink nometer Loadingfor Ink reading penereading (pounds pene- (percent tratlon (parentpolymer] tratlon reflee- (alter reflec- Handsheet ton pulp (Initial)tance) 15 days) terms) 16. 7 4 50 2 50 33. 3 1, 000 70 350 50 50. 0 I,000 79 686 50 66. 6 1, 000 90 970v 50 83. 3 808 50 674 50 100 287 50 28450 l 0 4 50 EXAMPLE 8 The elTectiveness of polymers prepared from PE]and dodecyl aziridinyl formate according to the procedure of example lwas evaluated for addition by the beater method. The polymers wereprepared from 90 percent by weight PEI and I percent by weight dodecylaziridinyl forrnate (product A),

70 percent by weight PEl and 30 percent by weight monomer (product B),and 50 percent by weight PEI and 50 percent by weight monomer (productC). The polymers were added to a slurry containing an unbleached sulfitespruce pulp (230 ml. Canadian Standard Freeners), in a concentration of1.2 g. pulp/180 ml. slurry. The polymers were added to the slurry andthe resulting mixture stirred for 30 seconds. Handsheets were made andevaluated by the ink penetration test as in example 7, immediately andafter 6 days of storage.

For comparison, a commercial sizing agent (Cyron size) sold by theAmerican Cyanamid Company, New York, N. Y., and identified as thereaction product of stearic acid and a polyalkylenepolyamine, wasevaluated under the same conditions. The results are shown below intable ll.

l 50% reflectance after 8 days at 25 C.

A polymer product prepared from 4i percent by weight PE] and 59 percentby weight dodecyl aziridinyl formate gave good sizing results but wasnot stable in water. A polymer product prepared from 26 percent byweight PEI and 74 percent by weight dodecyl aziridinyl fonnate was evenless stable in water. Solids precipitated from the solution, and itcould not be checked for sizing.

What is claimed is:

l. A water-soluble polymer consisting essentially of the reactionproduct of from 10 percent to 50 percent by weight, total reactant basisof Ai-l: an activated aziridinyl monomer having the structural formula i/CHB: V. \l

5. The process defined y claim 2 wherein A is sai epoxy monomer.

6. The process defined by claim 5 wherein A has the structural fonnulawherein R is alkyl, aryl, alkaryl or acyl.

7. Paper sized with the water-soluble polymer defined by claim 20.

8. The process of claim 2 wherein the polyalkylenimine has a molecularweight of at least about 3,000 and is combined with the activatedaziridinyl or epoxy monomer in the presence of an inert solvent in whichthe polyalkylenimine and the activated aziridinyl or epoxy monomer aredispersible.

9. A water-soluble polymer product of the process of claim 8 10. Papersized with a water-soluble polymer product.

produced by the process of claim 8.

11. The process of claim 8 in which the polyalkylenimine ispolyethylenimine, and the epoxy or activated aziridinyl monomer is,respectively, l-(p-dodecylphenoxy)-2,3-epoxy propane,l-(o-sec-butylphenoxy)-2,3-epoxy propane, 3-(2,3- epoxypropoxy)-2-hydroxypropyl stearate; or dodecyl laziridinyl carboxylate ordidecyl l-azin'dinyl phosphonate.

12. The water-soluble polymer defined by claim 1 wherein (A) is saidepoxy monomer.

13. The water-soluble polymer defined by claim 12 wherein R isdodecylphenyl, stearoyl, or o-sec-butylphenyl.

14. The water-soluble polymer defined by claim 12 wherein (B) ispolyethyleneimine or polyethylenepolyamine.

15. The water-soluble polymer defined by claim 14 wherein R is dodecyl,stearoyl, or o-sec-butylphenyl.

16. The water-soluble polymer defined by claim 1 wherein (A) is saidactivated aziridinyl monomer.

17. The water-soluble polymer defined by claim 16 wherein Y is oxygen.

18. The water-soluble polymer defined by claim 17 wherein R is hydrogen.

19. The water-soluble polymer defined by claim 16 wherein (B) ispolyethylenimine and polyethylenepolyamine.

20. The water-soluble polymer defined by claim 19 wherein Y is oxygen, Ris hydrogen, and R is dodecyl.

Po-wfio TE STA i Mei Patent No. 3, 359 Dated 18' January 1972Inventor(s) Juan Longoria, III and William P Coker It is certified thaterror appears in the above-identified patent and that said LettersPatent are hereby colg'rected as shown below:

Column 8, line 30, delete "claim 20.." and insert -cle.im l.--

Signed and sealed this 29th day of August 1972.

(SEAL) Attesti EDWARD M.FLETC HER ,JR. ROBERT GOTTSCHALK AttestingOfficer Commissioner of Patents

2. A process for producing the water-soluble polymer defined by claim 1comprising reacting by contacting (A) said activated aziridinyl monomeror epoxy monomer with (B) said polyalkylenepolyamine orpolyalkylenimine.
 3. The process defined by claim 2 wherein A is saidactivated aziridinyl monomer.
 4. The process defined by claim 3 whereinR3 is alkoxy.
 5. The process defined by claim 2 wherein A is said epoxymonomer.
 6. The process defined by claim 5 wherein A has the structuralformula wherein R is alkyl, aryl, alkaryl or acyl.
 7. Paper sized withthe water-soluble polymer defined by claim
 20. 8. The process of claim 2wherein the polyalkylenimine has a molecular weight of at least about3,000 and is combined with the activated aziridinyl or epoxy monomer inthe presence of an inert solvent in which the polyalkylenimine and theactivated aziridinyl or epoxy monomer are dispersible.
 9. Awater-soluble polymer product of the process of claim
 8. 10. Paper sizedwith a water-soluble polymer product produced by the process of claim 8.11. The process of claim 8 iN which the polyalkylenimine ispolyethylenimine, and the epoxy or activated aziridinyl monomer is,respectively, 1-(p-dodecylphenoxy)-2,3-epoxy propane,1-(o-sec-butylphenoxy)-2,3-epoxy propane, 3-(2,3-epoxypropoxy)-2-hydroxypropyl stearate; or dodecyl 1-aziridinyl carboxylateor didecyl 1-aziridinyl phosphonate.
 12. The water-soluble polymerdefined by claim 1 wherein (A) is said epoxy monomer.
 13. Thewater-soluble polymer defined by claim 12 wherein R is dodecylphenyl,stearoyl, or o-sec-butylphenyl.
 14. The water-soluble polymer defined byclaim 12 wherein (B) is polyethyleneimine or polyethylenepolyamine. 15.The water-soluble polymer defined by claim 14 wherein R is dodecyl,stearoyl, or o-sec-butylphenyl.
 16. The water-soluble polymer defined byclaim 1 wherein (A) is said activated aziridinyl monomer.
 17. Thewater-soluble polymer defined by claim 16 wherein Y is oxygen.
 18. Thewater-soluble polymer defined by claim 17 wherein R2 is hydrogen. 19.The water-soluble polymer defined by claim 16 wherein (B) ispolyethylenimine and polyethylenepolyamine.
 20. The water-solublepolymer defined by claim 19 wherein Y is oxygen, R2 is hydrogen, and R3is dodecyl.